Rewinding apparatus for the single or multiple rewinding of web-like material



United States Patent [72] Inventor Hans Stoebi Uzwil, Switzerland [21 Appl. No. 741,403 [22] Filed July 1, 1968 [45] Patented Dec. 22, 1970 [73] Assignee Maschinenfabrik Benninger AG Uzwil, Switzerland a corporation of Switzerland [32] Priority July 3, 1967 [33] Switzerland [31 No. 9,434/67 [54] REWINDING APPARATUS FOR THE SINGLE OR MULTIPLE REWINDING 0F WEB-LIKE 3,343,761 9/1967 Rotter ABSTRACT: A rewinding apparatus for the single or multiple rewinding of a web of material, such as fabric, between driven winding rollers. During any given winding operation one roller functions as the windup roller and the other as the wind-off roller, and their function reverses during each subsequent rewinding operation. An infinitely variable friction drive cooperates with each winding roller. Each friction drive incorporates a drive disk and a driven or power takeoff element, for instance in the form of a pivotably and rotatably mounted spherical segment. Regulator means serve to automatically control the friction drives in accordance with the progression of the winding operation, such regulator means being controlled by the changes in the web-length appearing between the winding rollers. The spherical segments can be pivoted by the regulator means through the same angle in order to selectively vary the point of contact of each drive disk at its associated spherical segment, and to thus also fulfill certain required proportionality relationships between the radii of the circular path of travel of the drive disks and the associated radii of the wound package of material.

INVENTOR. BY MM; 1722/ PATENIEDUEEZZHTB 3549100 sum 30! 3 FIG.6

' other as a wind-ofi roller.

REWINDING APPARATUS FOR THE SINGLE R MULTIPLE REWINDING 0F WEB-LKE MATE The present invention relates to an improved rewinding I machine or apparatus for the single or multiple rewinding of weblike material, especially fabric webs.

With the known full-width dyeing machines commonly referred to as jiggers, textile material, for instance, a web of I r fabric is unwound, generally a number of times, from one rotating roller to another rotating roller, and thus conducted through a dye bath. In so doing, one of the roller members E operates in reversible function as a windup roller and the As is known for this operation, it is of extreme importance that both the windup speed as well as the tension to which the ""rnaterial is subjected, remain constant, because both of these factors are of decisive importance for uniform dyeing. A

Euniformor constant tension of the material during the rewinding operation at the jigger is, however, also important for sublsequent processing, because, for instance, with fluctuating .tension, wound up webs of material have an irregular width [which leads to skeins'or hanks with uneven side surfaces.

These irregularities of the windup velocity or speed and the jniaterial tension during the course of the winding operation result from the fact that the peripheral velocity of the hank appearing at the windup roller continually increases whereas the peripheral velocity of the wound package at the other roller continually decreases during payoff.

A series of apparatuses are known to the art for obtaining the desired constant or uniform windup speed and material tension'during the rewinding operation. Some of these prior constructions operate on a purely mechanical principlewith infinitely variable frictional drives which can be adjusted by control drives influenced by the rewinding operation, whereas others, however, employ a purely electrical drive with speed-and-torsion regulators, or controls, or hydrostatic drives. Q

1 These known rewinding machines are, however, generally associated with the drawback that they can only approximately fulfill the requirement of uniform-tension of the material and web velocity during the rewinding operation. What is particularly apparent with rewinding machines operating on a purely electrical basis is that the structural expenditure and the cost thereof is in no proper relation to the success which is obtained.

SUMMARY OF THE INVENTION Accordingly, it is a primary object of the present invention is provide an improved rewinding apparatus which effectively overcomes the aforementioned drawbacks of the prior art structures.

Another more specific object of the present invention relates toan improved rewinding machine which insures for a constant web velocity and tension, even when working with ver sensitive webs of material, and while employing the simplc sttechnical, economical and reliable construction for such apparatus.

Still a further noteworthy objectof this invention relates to anlimpro'ved rewinding machine of the aforementioned type which is extremely reliable in operation, relatively uncomplicated in structure and economical to manufacture and not readily subject to breakdown.

Now, in order to implement these and still further objects-of the invention, which will become more readily apparent as the description proceeds, there is provided the inventive rewinding a'pparams for the single or multiple rewinding or weblike material from one driven winding roller to another driven winding roller, and vice versa, whereby the rewinding drive occurs by means of a drive motor via a respective infinitely variable friction drive associated with each winding roller. Furthermore, for the automatic control of the friction drives in accordance with the progression of the winding operation, there is provided a control device which is regulated or controlled by the changes in the web-length between the winding rollers. Accordingtothe invention, each of the two friction drives whichare of the same construction consists of a drive disc and a driven or power takeoff element formed by a spherical segment. The power takeoff element is pivotable'about the geometric axis of the spherical segment which axis is perpendicular to the plane containing the shaftmember for the drive discs and is rotatable about a shaft member situated in this plane. The rotational axes of both power takeoff elements are always guided parallel to one another. The point of contact between the drive disc and power takeoff element at both friction drives is selected such that the radius from the'piuot axis of the power takeoff element to this point of contact in the mentioned plane encloses an angle of +45 with a perpendicular connecting line between the pivot axis and the drive disc shaft in this plane at one friction drive, and at the other friction drive encloses an angle of 45. Furthermore, by means of the control device, both power takeoff elements are pivoted through the same angle in accordance with the takeup of material through its path of travel, and thereby the relationship or ratio of the radii of the circular path of travel of both drive discs driven with the same speed and the power takeoff elements associated therewith is always maintained proportional to the relationship or ratio of the associated radii of the wound package,

Whereas, known rewinding machines, in which for instance, the one element of the infinitely variable friction drive is formed by a conical surface, required a special control drive in order to compensate, during rewinding, the difference between the courseof the ratio of the rotational speed of both friction drives and the required course of the ratio of the rotational speed of the winding rollers, with the inventive rewinding machine or apparatus, such a special correction device can be dispensed with. This is so because in this instance the friction drives exhibit the same course of the ratio or relationship of the rotational speed because of their spherical segment-like power takeoff elementsas the winding rollers during the rewinding with constant web speed.

BRIEF DESCRIPTION OF THE DRAWINGS The invention will be better understood, and objects other than those set forth above, will become apparent, when consideration is given to the following detailed description thereof. Such description makes reference, to the annexed drawings wherein:

FIG. 1 is a vertical sectional view through a preferred embodiment of rewinding apparatus, taken along the line 1-1 of FIG. 2;

FIG. 2 is a top plan view, partly in section, of the rewinding apparatus of FIG. 1;

FIGS. 3 to 5 schematically depict different operating conditions during the rewinding operation; and

FIG. 6 graphically provides a geometric explanation of the principles of the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Describing now the drawings, it will be understood that the web of material which is to be rewound is generally designated by reference character B. This web of material B is unwound from a first driven winding roller la onto a second driven winding roller 1b and then unwound in the reverse direction and, in known manner, is conducted between both rollers 10 and lb through a suitable treatment liquid located in a nonillustrated vat or the like. In so doing, the web of material B is guided or trained about a pendulum or floating roller 31 secured to one arm of a lever member 32, the pivot point of which is designated by reference numeral 33. The desired tension of the web of material B between both of the winding rollers la and lb is adjustable by means of a cylinder unit 34 acting upon the lever member 32.

The momentary or instantaneous radii of the web of material 8 wound upon both winding rollers la and 1b are designated by reference characters Ra and Rb (FIGS. 3 through Driving of both winding rollers la and 1b takes place by means of a suitable drive motor 35, which is common to both winding rollers la and 1b, and which drives a shaft member 38 through the agency of the bevel gears 36 and 37. Two similarly constructed drive plates or discs 2a and 2b are mounted upon the shaft member 38. Each of these drive discs 2a and 2b forms a respective member of two friction drives for driving the winding rollers la and lb. Each of these drive discs 20 and 2b cooperates with a power takeoff element 30 and 3b, respectively, possessing the form of a spherical segment. A respective radially extending shaft 40 and 4b is secured to the inner surface of each spherical segment 3a and 3b, respectively. More specifically, these shafts 4a and 4b are mounted in such a way that they are situated in a plane which also contains the shaft member 38. In FIG. 1 this plane coincides with the plane of the drawing.

Continuing, it will be recognized that these shafts 4a and 4b each extend within a respective tubular member or pipe 5a and 5b, and are rotatably mounted therein at the bearings 6a and 6b, respectively. These tubular members 5a and 5b are each carried by a transversely extending tubular member 7a and 7b, respectively (FIG. 2), these tubular members 7a and 7b thus extending perpendicular to the previously mentioned plane. The central axis of each tubular member 7a and 7b passes through the center of the associated power takeoff element 3a and 3b, respectively. Furthermore, both of the tubular members 70 and 7b are rotatably mounted at the frame or housing 39 (FIG. 2) of the illustrated apparatus, so that each of the power takeoff elements 3a and 3b is pivotable about its diameter which is perpendicular to the previously mentioned plane containing the drive shaft 38 for the drive discs 2a and 2b.

Furthermore, respective shaft members 8a and 8b are mounted in the tubular members 7a and 7b, respectively, at the bearings 9a and 9b, respectively. A respective bevel gear 10a and 10b is seated upon the shaft members 80 and 8b. The bevel gears 10a and 10b mesh with the bevel gears 11a and 11b, respectively, seated upon the shaft members 40 and 4b, respectively. Each of the two shaft members 80 and 8b is in operable driving relation with one of both winding rollers 1a and 1b.

Additionally, the tubular member or pipe 7b carries a gear or toothed segment 40 externally of the power takeofi element 3b and with which meshes a worm 41 of a control or regulator device 42. By means of a rod member 43 which opcrably interconnects both power takeoff elements 3a and 3b with one another it is thus possible by means of the control device 42 to vary through the same angle the pivotal position of both spherical segments 3a and 3b about their associated pivot axes (defined by members 7a and 7b) and thus, as will be explained more fully hereinafter, to change the momentary circular path of travel of the drive discs 2a and 2b at their associated spherical segments 3a and 3b, respectively. Actuation of the control device 42 takes place in known manner through the agency of a rod member 44 engaging with the lever member 32.

A precondition or prerequisite for a unifonn tension and speed of the fabric web B during its throughpassage through the treatment liquid during a rewinding operation, is that there occurs a change in the driving speed or velocity of the rollers la and lb in accordance with the changing radii Ra and Rb of the material carried on these rollers la and lb, respectively. The rotational speed is only the same for both winding rollers la and lb at that moment of time in which exactly one-half of the web B is rewound from the one to the other winding roller, in other words, when Ra=Rb. This situation is illustrated in FIG. 3. The basic setting or adjustment of the rewinding apparatus must take place in such a manner that with the desired web tension in this situation both rollers are driven with the same speed. This presupposes that during this period of time the circular path of travel of the drive disc 20 at its associated spherical segment 3a is equal to the circular path of travel of the drive disc 2b at its spherical segment 3b. The radii of the momentary circular paths of travel are depicted in FIGS. 3 to 5 by reference characters r and r,,. These radii of the respective circular path of travel vary with the momentary pivotal position of the spherical segments 30 and 3b about their associated pivot axis 7a and 7b according to the equation:

r T constant In FIG. 6, in which for the sake of simplicity both of the spherical segments are shown in overlying relationship, it will be recognized that this equation is satisfied when the drive discs 2a and 2b, respectively, are arranged in such a manner at their associated spherical segment 3a and 3b that the radius from the pivot axis of the relevant power takeoff element to the point of contact of the drive discs 20 and 2b, respectively, in the plane containing the shaft member for the drive discs encloses an angle with a perpendicular taken from the pivot axis to the shaft member for the drive discs disposed in this plane at one friction drive which amounts to +45 and at the other friction drive encloses an angle of 45, and at the same time both spherical segments 3a and 3b are pivoted into a position in which their associated axis of rotation is perpendicular to the shaft member 38 for the drive discs 20 and 2b. This situation is illustrated in FIG. 3.

The sum of the volumes of material which at any time is located upon the winding rollers 10 and 1b is always constant and equals the total volume of the material to be rewound, namely:

V +V =constant (1) i In corresponding manner the end surfaces of the package or wound material located upon the winding rollers is constant:

R -i- R constant, (2)

wherein F and F,, represent the areas of the end surfaces of the fabric wound upon the respective winding rollers.

Since the selected fabric velocity or speed remains constant, at this period of time there occurs the following conditions:

and

V 21R}, 4t

wherein, n represents the momentary speed of rotation of the left winding roller and n the momentary rotational speed of the right winding roller (FIG. 3). From this relationship it is possible to derive the following equations:

Substituting equations 3 and 4' in equation 2 results in the following:

V 2 1 V 2 1 (Z) g =constant or, with V=c0nstantz 1 l constant With the inventive drive the shaft member 38 is driven with a rotational speed n,,. The diameters d, of the friction discs 20 and 2b are likewise constant.

The momentary peripheral velocity at both contact locations A of the power takeoff element 3a and A of the power takeoff element 3b (FIG. 6) are equal and amount to:

The thus resulting momentary rotational speed for the power takeoff element 3a amounts to:

o a' a and for the power takeoff element 3b:

b-n'b Since, however, the power takeoff elements are directly connected or via a drive having a fixed speed reduction relationship, with the winding rollers 1a and 1b, the following equation can be written for the power takeoff element 3a:

V =f-n -r,, (8) and the following equation for the power takeoff element 3b:

o=f'"b- 'b Furthermore, with the same package or winding radii R and R, (FIG. 6) of the following relationship holds true:

AABC=AABC' from which follows:

AABC=AAB"C' from which follows:

rib=constant Each variation or change of the speed of the fabric material owing to an increasing package diameter at the one winding roller and decreasing package diameter at the other winding roller during the rewinding operation influences the pendulum or oscillating roller 31 and raises such. This upward movement is transmitted by means of the lever member 32 and the rod member 44 to the control device 42 and the deviation from the reference value is utilized by the worm 41 via the gear segment 40 to bring about a pivoting of the spherical segment 3b about the axis 7b and via the rod member 43 interconnecting the spherical segments 3a, 3b a pivoting of the spherical segment 3a through the same angle.

In FIG. 4 there is depicted the extreme situation in which the winding roller 1b has been unwound so that it is practically empty and almost the entire web of material B is located upon the winding roller 1b.

In FIG. 5 there is depicted the reverse situation where the roller la is practically empty.

Now, if from equation 8 there is derived the following equation:

and if these new equations 8' and 9' are substituted in equation 10, then there results:

. =constant n n between the rotational shaft of one winding roller and that of the associated power takeoff element.

It should be apparent from the foregoing detailed description, that the objects set forth at the outset to the specification have been successfully achieved.

1 claim:

1. A rewinding apparatus for the single or multiple rewinding of weblike material from one driven winding roller to another driven winding roller, and vice versa, comprising drive means for carrying out the rewinding operation, said drive means incorporating a drive motor and a respective infinitely variable friction drive associated with each winding roller, regulator means controlled by the changes in the weblength between the winding rollers for the automatic regulation of the friction drives as a function of the progression of the winding operation, both of said friction drives being similarly constructed, each friction drive incorporating a drive disc and a power takeoff element constructed as a spherical segment, shaft means for operably interconnecting said drive discs, each said power takeoff element being pivotable about the geometric axis of its spherical segment, said geometric axis being perpendicular to a plane containing said shaft means for the drive discs, a respective shaft means disposed in said plane for providing an axis of rotation for each power takeoff element, the axes of rotation of both power takeoff elements being guided parallel to one another, the point of contact between each drive disc and its associated power takeoff element for both friction drives being chosen such that a radius taken from said axis of pivoting of one power takeoff element to such point of contact in said plane encloses an angle of +45 with a perpendicular connecting line taken from said axis of pivoting to the shaft member for said drive discs located in said plane at said one friction drive and an angle of 45 at the other friction drive, said regulator means serving to pivot both power takeoff elements through the same angle in accordance with the takeup of material through its path of travel, so that thereby the ratio of the radii of the respective circular path of travel of both said drive discs driven with the same speed at the associated power takeoff element is always maintained proportional to the ratio of the associated radii of the wound package.

2. A rewinding apparatus as defined in claim 1, further including means for controlling said regulator means.

3. A rewinding apparatus as defined in claim 2, wherein said controlling means for said regulator means comprises a pendulum roller.

4. A rewinding apparatus as defined in claim 1, further including tubular means provided for each power takeoff element and defining said geometric pivot axis of the associated power takeoff element, a respective shaft rotatably mounted at each tubular means and which provides the power takeoff shaft of the associated friction drive, and gear means for operably interconnecting said power takeoff shaft with said associated shaft member providing said axis of rotation of the associated power takeoff element.

5. A rewinding apparatus as defined in claim 4, wherein said shaft members providing said axis of rotation of each associated power takeoff element are each arranged in a further respective tubular member, each said further tubular member being carried by said tubular member defining said pivot axis.

6. A rewinding apparatus as defined in claim 4, wherein said gear means comprise bevel gears. 

